Pivoted knife blade assembly



Jan. 20, 1953 F. E. GRUBER 2,625,738

PIVOTED KNIFE BLADE ASSEMBLY Filed March 24, 1947 2 SHEETSSHEET l Zmnentor FRANCIS E. GRUBER (Ittorneg Jan. 20, 1953 v F. E. GRUB ER 2,625,738

I PIVOTED KNIFE BLADE ASSEMBLY Filed.March 24, 1947 2 SHEETSSHEET 2 29 2| 27 28 lo II I "T i I} A 12 O A II lfsnoentor FRANCIS E. GRUBER Gttomeg Patented Jan. 20, 1953 UNITED STATES 'ATENT OFFICE PIV OTED KNIFE BLADE ASSEMBLY Francis E. Grnber, St. Paul, Minn, a'ssignor "to Brown :& .Bigelow, St. Paul, Minn.

Application'M'arch 24, 19 47,.SerialNo. 736,664

3-Claims. 1

My invention relates to 'a'm'ethod of making knife blades and assembly unit,'wherein the knife blade may be made of thin sheet steel and its base mounted between clamping plates which strengthen the base and provide the spacing means on either side thereof, so that the blade may be mounted within an assembly unit which, in turn, is adapted to be supported within a casing.

A feature resides in forming a pair of plates with openings therethrough to permit the plates to be riveted to the base of the blade and "to provide a shoulder along one edge of the plates which engages under the "longitudinal edge of the base of the blade.

The method consists in forming a blade out of very thin sheet steel to provide the outline thereof and then form a sharp edge thereon, after which a pair of metal plate members (not necessarily steel) are formed in a shape to fit the base of the blade and providing inturned flanges on the plate members and then anchoring the plate members by a rivet to the base of the blade.

the base thereof, it is then adapted to be pivotally anchored between the sides of .a U-shaped unit support in which the spring for engaging the back of the blade to hold it in open or closed secured to its base and pivotally positioned within the U-shaped plate unit with the blade positioning spring.

Further features and objects of the invention will be hereinafter pointed out.

In the drawings forming part of the specification:

Figure 1 is a side view of a knife blade made by my method.

Figure 2 is a top edge view of the blade.

Figure 3 illustrates one of the side plates, in elevation, showing the shape of the plate which forms a reinforcing at the base of the blade when it is attached to the same.

Figure 4 is an edge view of the plate shown in Figure 3.

Figure 5 shows the blade with the step of the method carried out which attaches a pair of the reinforcing plates to the base of the blade.

Figure 6 is a rear end view of Figure 5.

When the blade has been thus 7 formed with the reinforcing plates anchored to 2 Figure 7 is a bottom edge view of Figure '5 looking at the sharp edge of the blade.

Figure 8 is a perspective of the blade attached to the unit support, showing a further step of the method.

Figure 9 is a side view of the blade and unit shown in Figure 8.

Figure 10 illustrates another step of the method which "includes the anchoring of the knife blade unit support anchored in one end of a tubular casing.

Figure 11 is a section "on the line ll-"H of Figure 10 in the direction of thearrows.

The method includes stamping a knife blade is out of thin sheet steel and forming the blade with a sharp edge II and a fingernail groove l2.

The blade In is formed with a recess I3 which is adapted to be engaged by a spring which will be hereinafter set forth.

The base of the blade I4 is provided with a large hole l5 and a smaller hole i6 spaced inwardly from the hole [5. This method includes the reinforcing of the base of the blade M by rigidly anchoring two reinforcing plates I! to the sides of the base by an anchoring rivet I8 which extends through the plates l1 and the hole It and has its ends riveted over to securely fix the plates H to the sides of the base M. The plates l1 form spacers as well as reinforcing means, which spacers support the blade and strengthen it and permit it to pivot in the U-shaped unit support A. A tubular hollow rivet I9 pivotally anchors the blade In between the sides 29 of the unit support A.

The plates [1 are formed with inturned flanges 2| which engage against the lower edge 22 of the base l of the blade. The plates [1 are died out in the form and the shape of the base [4 of the blade, and by means of the rivet l8, the plates ll are anchored firmly in place and in line with the outline of the base of the blade l4.

When the blade I0 is completely formed and finished, it includes the base plates I! which may be made of brass or softer steel than the blade; thus, the plates I! add the necessary thickness to the blade [0 and permit the forming of the blade ID of a high quality of thin steel which makes the blade flexible, strong and tough and which overcomes the necessity of first forging the blade out of heavy steel and then grinding it to a thin blade with a heavy base. This method is more economical than old processes of forming blades and permits the use of the very best grade of thin flexible steel which is desirable for knife blades.

When the blade I is completed by my method and the plates [1 are rigidly attached, it is ready to be anchored pivotally by the rivet IS in the unit support A.

The unit support A includes a one-piece U-shaped channel with sides 20. At one end of the channel of the unit A, the rivet l9 holds the blade I0 pivotally supported to the unit. At the other end of the unit channel A, a spring 23 is anchored by the rivet 24. The spring 23 is provided with an arm 25, the free end 26 of which engages in the notch l3 of the blade l0 and the plates [1. Thus, the blade I0 is held under spring tension either in open position or in closed position. When the knife blade 10 is in closed position, it is folded between the sides 20 of the unit support A.

The unit support A, together with the blade assembly, is adapted to be anchored by the single rivet 21, shown in Figures 10 and 11, which holds the unit'A within the tubular casing 28, as illustrated in Figures 10 and 11.

Notches 29 and 30 formed on opposite sides and ends of the unit A are adapted to be engaged by the tubular casing 28 to hold the unit A rigidly within the casing. Within the casing 28, I provide filler plugs 3| which may be made of plastic or any other suitable material and which are adapted to form a finished end for the casing 28 which supports the knife blade unit A.

Thus I provide a method of assembling knife blades made from thin sheet steel and supported within a unit which is held by a single rivet within an outer casing or handle 28.

The lower edge of the notch 29 engages underneath the inner surface of the casing 28 at the end of the opening formed on the edge of the casing 28. The opening in the casing 28 is ,shown more particularly in Figure 11 of the drawings. Theedge of the notch 29-formed at right angles to the above mentioned lower edge of the same abuts againstthe end of the slot formed in the casing 28, thereby prohibiting upward movement of the unit support A. The notch 30 formed in the unit A abuts the outer edge of the casing 28, thereby positioning the unit A in the casing in conjunction with the positioning of the notch 29. In Figure 10, the notch 29 is shown in dotted lines abutting the end of the slot formed in the casing 28, the inner surface of the casing 28 being shown in dotted lines.

The transverse rear end of the unit A is shown in dotted lines in Figure 10, indicated at l|l in Figure 10. T

I claim I '1. A knife blade unit assembly including a knife blade formed of thin steel, reinforcing plates positioned on either side of the base of -said plates to said blade said blade, a rivet fixing said plates to said blade, inturned flanges on the lower edges of said plates engaging the lower edge of the base of said blade, a one-piece unit channel support for said blade, a hollow rivet pivotally supporting said blade in said channel, a casing for supporting said blade and channel, and a rivet extending through said blade, plates, hollow rivet and casing to pivotally support said blade and to secure said channel unit within said casing.

2. A knife blade and supporting channel unit including a U-shaped channel formed from a single piece of sheet metal, a blade pivotally supported in one end of said channel by a hollow rivet, a spring for engaging said blade to hold the same under spring tension in open or closed position in relation to said channel, blade spacer plates positioned on either side of the base of said blade and secured thereto by a rivet, said plates conforming to the outline of the base of said blade, projecting flanges formed on said plates adapted to engage the lower edge of the base of said blade, the upper and lower ends of a casing having an elongated opening formed therein for enclosing said channel blade unit, a single rivet adapted to extend through said hollow rivet to anchor said channel blade unit in said casing, and notches formed in the upper ends of said channel farthest from said hollow rivet and in the lower end of said channel adjacent said rivet, respectively, said notches acting against the forward edge of said casing and the rear edge of said elongated opening to position and rigidly hold said channel in said casing.

3. A knife blade unit including a central knife blade portion of thin steel, a plate member for each side of the rear end of said blade portion, inturned flanges formed on the lower edges of 'said plate members engaging the lower edge of the base of said blade portion, and a rivet fixing portion.

FRANCIS E. GRUBER.

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